Fluorescent lamp circuit



P 1949- L. J. NEVILLS FLUORESCENT LAMP c'mcun Filed Oct. 16. 1947 NVENTOR;

FIG. 3

. FIG

\1 w WNEII HIS Ai'ToRNEYs Patented Sept. 27, 1949 UNITED STATES PATENT OFFICE FLUORESCENT LAMP CIRCUIT Lester J. Nevills, Lemay, M0,, assignor of onehalf to Stupp Bros. Bridge & Iron Company, St. Louis, Mo.', a corporation of Missouri Application October 16, 1947, Serial No. 780,195

This invention relates to control circuits and in its more specific aspects is directed to a control circuit for fluorescent light fixtures.

The object of this invention is to provide a control circuit for fluorescent light fixtures wherein a single timing unit will control the lighting of a plurality of light fixtures.

Another object of the invention is to provide a control circuit in which one time delay relay circuit will control the disconnection of the heating elements for the several fluorescent fixtures and in which the time for the delay relays operation may be varied to suit individual fixture requirements.

In the drawings: a

Fig. 1 is a circuit diagram incorporating the invention,

Fig. 2 is an elevational view of a portion of a switch control panel; and

Fig. 3 is a section view taken along the line 33 of Fig. 2.

Referring now to the drawings, numeral I designates a transformer which is excited from a suitable source of current of preferably 220 volts, indicated generally by conductors 2 and 3 for the circuit beginning with conductors 4 and 5 through switches 6 and I which may be of any suitable type.

The timing mechanism for the control circuit consists of a relay 8 and a rectifier tube 9, the rectifier filament being heated from a secondary winding on transformer with the rate of heating being controlled by a rheostat ID. The output side of the plate circuit for the rectifier is connected to the electromagnet of the relay 8 in the customary manner. The armature for the relay 8 opens and closes a switch II in the circuit for the panel switch operating solenoid |2. The armature I3 for solenoid I2 is mechanically connected to a panel switching member M by linkage l5. The member M has a strip of insulation I4 secured thereto, all of which extends the full length of the panel board IS. The panel board is only schematically illustrated in Fig. 1 but is more completely detailed in Figs. 2 and 3.

A plurality of switch blades l1, l1, etc., are rigidly mounted on but insulated from the panel l6 by suitable securing means and a plurality of fixed switch contacts l8 (only one of which is shown) is secured to the panel. A member I9 is laid across the upper end of the blades to assist in keeping them in position. A plurality of fixed contacts 20 equal in number to contacts I8, is also mounted in the panel board and fixtures 2| 11 Claims. (Cl. 315-97) 2 are connected between each set of contacts I8 and ZB.

Contact 20 extends through the panel board l5 and is engageable with a movable contact 22 mounted on switch blade ll. Contacts 22 and 2|) are separated by solenoid armature l3 through linkage connection I5 and a suitable spring (not shown) customary in the art may be employed to return solenoid E3 to inoperative position.

An auto or ballast transformer 23 is connected across conductors 4 and 5 in the manner illustrated by conductors 24 and 25. The lamp bulbs 2|, 2| are each provided with starting heating elements 25, 27 and 28, 29, respectively. The starting circuit for heating elements 26 and 21 consists of conductors 30, 3| heating element 26, conductor 32, contacts 20, 22, switch blade contact |8, conductor 36, heating element 21, and conductor 35 to the transformer. The circuit for heating elements 28 and 29 consists of conductor 30, heating element 28, conductor 33, contact l8, blade l1, contacts 20, 22, conductor 31, heating element 29, and a conductor 34 to the transformer.

These circuits remain closed until the starting elements have been sufiiciently heated. the time therefor being determined by the rheostat for the delay relay 8, previously described. When relay 8 closes switch solenoid I2 is energized, whereupon contacts 22 and 20 (Fig. 3) separate to thereby impose a potential across respective heating elements 26, 27 and 28, 29 or across the entire fixture to keep the fluorescent bulbs 2|, 2| charged and illuminated as long as this potential is maintained, the heating elements functioning as electrodes during. normal illumination of bulbs 2|, 2|.

Switch blades I1 and i 1 are not shown connected to any fixtures but by the provision of another ballast or auto transformer, additional light fixtures may be connected to the panel board contacts associated with blades I1" and I?" in the manner just described. Any number of lamp bulbs 2|, 2| may be connected to a single panel board and all may be controlled by a single time delay relay 8. The connection described has been found to be very reliable under various temperature conditions working equally well in cold as well as in very warm temperatures. Flickering of lights has also been eliminated because each heating unit is subjected to constant and unvarying conditions, starting time has been shortened and illumination improved with the above described circuit.

What I claim is:

1. A control circuit for a plurality of light fixtures comprising a transformer; a pair of light bulbs having a pair of heating elements in each bulb; a switch panel having a plurality of pairs of switch blades thereon; circuit means to connect the heating elements in each, lamp, the switch blades and the transformerso that there is a separate circuit for each lamp and one of said blades; a relay to simultaneously actuate said switch blades to disconnect said elements and to simultaneously impose a voltage acmfii each of said lamps; and a time delay mechanism to operate said relay.

2. A control circuit for a plurality ofrlight .fix-

tures comprising a transformer; a plurality of pairs of light bulbs; a pair-of heatingelements in each bulb; means to connect the heating,;.ele-L ments for each lamp into a circuit with said transformer and impose a voltage across each element; a panel having a plurality of switch means thereon with one switch means in each c rcuit to open ame to thereby im ose a o tage acrosseach lamp; anato ope ate said switch; andmeans to operate saidlastmentioned means a predetermined time after said circuit is closed.

3. A control circuitnfor a plurality of light f tures comprising atransformer; a light bulb havins apa r. of eating l e er i me to connectsaid heatingelements tosaid transformer tolim Q a v ta e ac Q a hmemen means tovopen said; circuit andto simultaneously impose, a voltage across said; bulb; a relay to op a sa last mention d means; an means tocpera e saidw l y a predete e .t mea te said first mentioned means isoperative ,4. A control circuit for apluralityoi light bulbs nwhich e ch ul separa ely contrq ledlc mprising a paperboard p o idedwit a plurality of switch blades andto whichaplurality of; bulbs I is connected, each bulb provided with a. pair of heating elements; a circuit for each-b1 1 which includes both of said heating elements and one of said blades; a transformer to which saidcircuit is connected; a switch in said circuit: to control sameand to simultaneously impose a voltage across each bulb connectedto saidpanel; and means to open said switches a predetermined time after said circuit is closed to thereby im- 5 pose a voltageacross each bulb.

5. A- control circuit for-aplurality-of light bulbs in which eachbulb is separately-controlled comprising a panel board provided-witha plurality of switches to'which a plurality of bulbsisconsource; circuit means to. connectsaid'. transformer tq aidheatingelements whileconnected in series in order to heat same; a switch in said circuit; and means to open said circuit after it has been closed a predetermined length of time, said circuit being then arranged so that said voltage is imposed across the light bulbs to energize the bulbs.

'7. A control circuit for fluorescent light bulbs, each; provided with a pair of heating elements, comprising circuit means to connect said heating elements in series in order to heat same; a transformer to which said circuit is connected in order- .to energize same; a switch in said circuit; and means toopen said switch after it has been closed a, predetermined length of time, said circuit; being then arranged so that a voltage is bulbs.

8. Aiiuorescent light circuit switch operating mechanism comprising a transformer; a rectifier connected thereto; a relay operable by current derived from said rectifier; a switch-panel havin a plurality of switch elements thereon connectable in a light circuit; and means for simultaneously operating each of said switch elements controlled by said relay.

9. A flourescent light circuit switch operating mechanism comprising a transformer; a rectifier connected to said transformer; a, relay; operable by current derived fromsaid rectifier; a switch panel having a plurality of switchblades thereon connectable in lamp circuits; a solenoid for simultaneously operatingeach of said switch blad es and controlled'by said relay; and means for varyll'lg the time required for the operation of'sald relay. 5 v A 10; A fluorescent light circuit switch operating mechanism comprising an alternating current supply; a transformer connected tosai-d supply; a rectifier connected to said transformer; a; relay includinga switching member and operatedby current derived from said rectifier; a switchpanel having a plurality ofsimultaneously cperated switch elements thereon; -a solenoid for simultaneously operating the-switch elements-ionsaid i panel; a circuit for saidsolenoidwhich-includes the switching member ou -said relay and connectable to said source of-supply when said relay is operated; and means for varying the operat ing-time of said relay.

11. A fluorescent light circuit switch operating mechanism comprising aswitchpanel having a plurality of'switch.bladesthereon;V a solehold "for simultaneously operating each of; said switch blades; a -relay.- forcontrolling .the operation of said; solenoid; means forcenergizinglsaid relay; and means for regulating the ,time re.- ui e fo i ener izing said; relay- 1J NEVILLS:

aaiia a tc r The -following references are of record-in the -file of this patent UNITED fs'ra'ras en'rnnrrs Number :Name Date ;2;19,5.;ll4 McCarthy Marg26, 1940 -2;27;2;770 :Edwards l Feb. 10,- 19.42 :2;33.4, 5 3fi Bryant; Nov. 16 19.43 2361- 017; Elioket, al Oct. '24,,I94l iii- 4 3 2 H dskins V V ;Apr. 24,119,451 

